title: In situ laccase treatment enhances the fermentability of steam-exploded wheat straw in SSCF processes at high dry matter consistencies.
abstract: This work evaluates the in situ detoxification of inhibitory lignocellulosic broths by laccases to facilitate their fermentation by the xylose-consuming Saccharomyces cerevisiae F12. Treatment of wheat straw slurries with laccases prior to SSCF processes decreased the total phenolic content by 50-80%, reducing the lag phase and increasing the cell viability. After laccase treatment, a negative impact on enzymatic hydrolysis was observed. This effect, together with the low enzymatic hydrolysis yields when increasing consistency, resulted in a decrease in final ethanol yields. Furthermore, when using high substrate loading (20% DM (w/v)), high concentration of inhibitors prevailed in broths and the absence of an extra nitrogen source led to a total cell growth inhibition within the first 24h in non-treated samples. This inhibition of growth at 20% DM (w/v) was overcome by laccase treatment with no addition of nitrogen, allowing S. cerevisiae F12 to produce more than 22 g/L of ethanol.
authors.affiliation: Instituto IMDEA Energía, Biotechnology Processes for Energy Production Unit, 28935 Móstoles, Spain.
authors.forename: Antonio D
authors.initials: AD
authors.lastname: Moreno
authors.forename: Elia
authors.initials: E
authors.lastname: Tomás-Pejó
authors.forename: David
authors.initials: D
authors.lastname: Ibarra
authors.forename: Mercedes
authors.initials: M
authors.lastname: Ballesteros
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Olsson
mesh_terms: D005285:Fermentation; D042845:Laccase / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D014908:Triticum / Q000378:metabolism*
chemical_list: D042845:Laccase
keywords: Bioethanol; In situ laccase detoxification; Lignocellulose; S. cerevisiae F12; Simultaneous saccharification and co-fermentation